Charge after a flight or before the next?

[Merlin83b]

Do people charge when they're done, storing the batteries full, or just before they next fly, storing the batteries at some lower level of charge? I've been storing them full so I'm ready to run out and fly but wonder if that's what's best for the batteries?

 

[msinger]

Batteries should be stored within the storage level. See more details here.

 

[Clinton1]

^^ as above, very good tip, and it helps keep your batteries in good shape. They will last much longer in the long run.

 

[BorisTheSpider]

Yeah that's exactly what I do to avoid unnecessary cycles - after use but once the batteries have cooled I charge until a third light is blinking (normally I set a timer on my phone for about 13 minutes, which gets me from about 25% where I normally land, to just over 50%).

If you land at 15% or whatever you'll probably need more like 20 minutes to get to 50%, probably best to time it the first time so you know how to set your timer.

As a bonus charging to 100% to fly the next time is then quicker.

 

[AlwaysAWOL]

If I know I'm flying the next day I'll charge two of my batteries up after flying and after they've cooled. I have a third that I don't use, just keep at storage level as a spare. Figure they should last me until the Mavic II Pro comes out with awesome new features and a higher end camera (please?!).

 

[rydfree]

I charge one of my batteries at the end of the day after flying and another a couple days after . Self discharge is set to 5 days . I keep the Mavic in the truck in case I see something interesting or just want to fly after work etc . If I don't have a charged battery then it's useless to me . This way I have a couple batteries charged for a few days and at least one over a weeks time but I don't think they have ever been allowed to self discharge .

 

[tcope]

Yeah that's exactly what I do to avoid unnecessary cycles - after use but once the batteries have cooled I charge until a third light is blinking (normally I set a timer on my phone for about 13 minutes, which gets me from about 25% where I normally land, to

Keep in mind, charging 25% is a charge. The reason batteries were out is because they go through the stress of a charge cycle (and then a discharge cycle as well). So you may be adding stress to the battery for a 25% charge. Might be better just to leave it at 30% and not putting that extra stress to get it to 50% or 75%. Just something to consider.

The worse think to a lipo battery is leaving it at 100% for a long time and taking it down to 0%. Since these are "smart" batteries, they won't stay at 100% for longer then a couple of weeks if not touched. If a battery is used every couple of months it's not likely that it will drain down to 0%. IMHO, these batteries are pretty well protected with those features. So I see the real issue as being number of charges. But I also don't see that as much of an issue if someone has 3 batteries or so and cycles them correctly.

 

[BorisTheSpider]

Keep in mind, charging 25% is a charge. The reason batteries were out is because they go through the stress of a charge cycle (and then a discharge cycle as well). So you may be adding stress to the battery for a 25% charge. Might be better just to leave it at 30% and not putting that extra stress to get it to 50% or 75%. Just something to consider.
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Thanks but I didn't mean I charge to 50% then use them. I charge from say 25% to 50%, then leave them stored until I plan to fly again when I charge the remainder of the way from 50% to 100% so there's only one charge cycle happening, it's just being split into two parts.

 

[tcope]

Thanks but I didn't mean I charge to 50% then use them. I charge from say 25% to 50%, then leave them stored until I plan to fly again when I charge the remainder of the way from 50% to 100% so there's only one charge cycle happening, it's just being split into two parts.

Yup, that is what I thought. I'm not saying this is absolutely correct but consider... what wears a battery is adding a charge to it. The chemical process happens and heat is generated. So (perhaps?) any significant charge has the same affect. So charging from 25% to $50 could be a cycle and then 50% to 100%, another cycle. Each time the battery is charged, up to a certain degree, that strain has already been placed on the battery. If that same strain continues for a little while longer, it does not make much more of a difference. So _perhaps_ charging 25% and then charging 50% is putting twice the strain/wear as one 75% charge.

 

[BorisTheSpider]

That's a thought but I'm not convinced - lots of traditional lipo chargers have a storage charging mode where they stop once the battery is partially charged.

I also think most of the stress on a lipo is in the deep discharge part of the cycle, and in the last 10% above 90%, so charging from a conservative landing %age like 25 up to about 50 is the least damaging part of the charging cycle.

 

[tcope]

That's a thought but I'm not convinced - lots of traditional lipo chargers have a storage charging mode where they stop once the battery is partially charged.

I also think most of the stress on a lipo is in the deep discharge part of the cycle, and in the last 10% above 90%, so charging from a conservative landing %age like 25 up to about 50 is the least damaging part of the charging cycle.

Yes, I am speculating a little. Having a storage charge would not change anything. It does not discount that this may put wear on the battery and possibly create a cycle.

So if it were something like the last 10% of of a charge that puts most of the wear on the batter, a person could only ever charge the battery and get a substance more amount of use from it? If that were the case, I could get unlimited use from a battery if I only ever charged it to 90%? Just throwing out some thoughts for the sake of debate.

Good info.

 

[BorisTheSpider]

Charging to 90% will actually substantially improve long-term battery health, but at the cost of losing some of the utility which in an aero application I don't think is a good trade off. If you're going to carry the weight of a given capacity battery you really need to get full use from it, but in other applications charging to less than completely full is a good idea.

 

[tcope]

Charging to 90% will actually substantially improve long-term battery health, but at the cost of losing some of the utility which in an aero application I don't think is a good trade off. If you're going to carry the weight of a given capacity battery you really need to get full use from it, but in other applications charging to less than completely full is a good idea.

Well shoot... I thought you might disagree with the 90% thing.

If it's correct, that charging to 90% would increase life, I'd agree that it would not be worth doing. Yes, saving that extra flight time would not be worth the extra cycles because truth is, with 3 or 4 batteries you are going to get 1200-1600 flights anyway which is probably going to last longer then most people would fly the Mavic anyway.

So I'd also agree that charging to 50% and then to 100% probably won't make a difference, really if a person has 3-4 batteries. Perhaps it might make a difference with 1 battery but if a person only has 1 battery... the problem is really that they need to buy more.

 

[BluesDragon]

How is 'storage' defined here? I mean, if you have 3 batteries, fully charged for play, you only use 2 of them and for whatever reason don't get to the 3rd one... is it safe to leave it full until the next day? Storing them at 50% is mainly for 'long term' storage... like a week or more... no?

 

[msinger]

if you have 3 batteries, fully charged for play, you only use 2 of them and for whatever reason don't get to the 3rd one... is it safe to leave it full until the next day?

Yes.

 

[BluesDragon]

Good to know... thanks msinger.

 

[geigy]

I charge them right after so I can be ready for the next time. If that's bad for the batteries, so be it. Life is meant to be lived.

 

[tcope]

How is 'storage' defined here? I mean, if you have 3 batteries, fully charged for play, you only use 2 of them and for whatever reason don't get to the 3rd one... is it safe to leave it full until the next day? Storing them at 50% is mainly for 'long term' storage... like a week or more... no?

Next day? Yes. For a week? Some people might disagree but I'd say that is fine. The important thing is your settings to discharge. The max minimum is 3 days, the max is 10 days. This means discharge to 60% would result around 6 - 13 days if not touched. So they will never stay charged more than 13 days or so if not touched. IMHO, discharging batteries is really not a big issue as they self discharge. Leaving a lipo battery at 100% or 10% for months _would_ be an issue. Leaving it at 100% or 30% for a month probably won't hurt much (as 100% would discharge to 60%).

 

[BluesDragon]

I charge them right after so I can be ready for the next time. If that's bad for the batteries, so be it. Life is meant to be lived.

This is pretty much how I've started out as well. Took everything (3 batts., RC, iPad) to full charge right out the box. After activating, initial setup, and getting familiar with the app and controls.. I'd only knocked 1 batt. down to 30% and the 2nd to maybe 35%. As it was dark out by then, the last battery I left full until today. Meanwhile.. I recharged everything else back up to 100% for today's test flight. I'm sure to be getting 'er out to play every other, if not every, day.

 

[BluesDragon]

Guess I should have added... "weather permitting, of coarse"... to the end there.